Issue with QL-SD and SGC

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Chr$
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Issue with QL-SD and SGC

Post by Chr$ »

Hello. I wonder if anyone has experienced this or can lend some pointers.

I recently setup a QL-SD with a Tetroid ROM switcher, it looks like this inside (fortunate that Sinclair had the foresight to offer 2 ROM sockets that are electrically the same back in 1983, because the devices won't fit on top of each other ;) ).
20210531_185514.jpg
I burned some appropriate images onto the ROM switcher inc MGG with the SD driver at C000h, JS with the SD driver, Minerva 1.98a1 with the SD driver (as supplied on MK's website) and also some of the same main ROMs accompanied by an older TK2 at C000h instead of the SD driver.

When I use a Super Gold Card (original one, ROM v2.49) in combination with the default QL-SD ROM setup of Minerva 1.98a1 and the SD driver I get random gibberish in file names and within files, like this:
20210601_165035.jpg
However, when I use Minerva 1.98a1 without the SD driver in ROM and then lrespr it manually, it's fine:
20210601_164401.jpg
It's also fine if I use the JS/SD driver combo or MGG/SD combos.


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Collector of QL related computers, accessories and QL games/software.
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mk79
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Re: Issue with QL-SD and SGC

Post by mk79 »

Yeah, that cannot work as-is. QL-SD must be able to disable the ROM, which is one of the reasons some legs are bent. What you see is the ROM switcher and QL-SD fighting for the data bus. You'd need to route the enable signal that comes out of one of the pins on the right side of QL-SD to the switcher. Not impossible but I don't think there is an easy way to do that.


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Chr$
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Re: Issue with QL-SD and SGC

Post by Chr$ »

mk79 wrote:Yeah, that cannot work as-is. QL-SD must be able to disable the ROM, which is one of the reasons some legs are bent. What you see is the ROM switcher and QL-SD fighting for the data bus. You'd need to route the enable signal that comes out of one of the pins on the right side of QL-SD to the switcher. Not impossible but I don't think there is an easy way to do that.
Understood!

For the moment then, I'll just boot from floppy (or mdv) and load the SD driver and TK234 from there before running the regular boot from win1_. Takes 30 secs longer than usual. I still have to use JS fairly often when dumping original carts, so I like to have a method of switching back to standard JS roots without having to keep opening it up.

I must say though, being able to use a QXL.WIN container on a real QL makes everything so much easier. That is simply the file format that you can use with everything nowadays and it's easy to swap over content etc. I copied the contents of the TDI CF card that I was using up to now to a fixed drive on the Q40 and then put the contents of that win partition into an empty QXL.WIN. So easy with the Q40 being able to handle the native format and the QXL.WIN container.

Thanks for your (and others) efforts on QL-SD.


https://QXL.WIN
Collector of QL related computers, accessories and QL games/software.
Ask me about felt pads - I can cut them to size and they have proved excellent for mdv data recovery.
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